What is NAT in Networking? A Complete Guide | Simplilearn

Network Address Translation (NAT), is a method designed to conserve IP addresses in a private network, by using a unique IP address to represent the whole private network to access internet services for the network model.

Be Prepared to For Any Ethical Hacking Interview!

PCP In Ethical Hacking And Penetration Testing

Explore Program

What Is Network Address Translation?

Network Address Translation is the network process that is the task of translating and assigning the private network model, to the global IP address to access internet services. 

The same step is repeated, to convert a public IP address into a private IP address, to provide the received data and information from the internet. The NAT process helps with the conservation of IP addresses and provides better security.

Let’s move on to the next heading in the article, which are addresses involved in the NAT process.

Addresses of NAT

NAT addresses can be differentiated as inside and outside addresses, where inside address refers to the private addresses to be translated. The outside addresses refer to as the ones used to access the internet.

Inside local address: This IP address represents the host of the private network. This address cannot be used by a private network to access the internet directly.

Inside global address: This IP address represents the whole private network, by using a globally recognized public IP address. It is used to access the internet services for the private network.

Outside global address: This IP address represents the outside network address for the host before the NAT translation process.

Outside local address: This IP address represents the actual address representing the host on the internet, after the NAT translation process.

Learn How to Secure, Test & Manage IT Systems

Advanced Executive Program in Cybersecurity

Explore Program

Working of NAT

The working of NAT begins with configuring the network router or NAT firewall, for the network translation to take place. The network router has an interface that acts as a connection between the inside (local) network, and the outside (global) network.

The inside network address has to go through the router for the translation process and gets converted to an outside globally recognized IP address to access internet services and the same translation process when moving from outside network to inside network.

Types of NAT

In accordance with the process of translation of network addresses, different types of NAT processes are available to the user to use for their network model, some of which are:

• Static NAT – In this NAT process, one single private network is mapped to an individual public IP address. This process of translation is also known as one-to-one NAT, used generally for private network connections.

• Dynamic NAT –  For this NAT translation process, the private network address is converted to a public IP address by choosing it from a pool of public IP addresses available to the network model.

• Port Address Translation – This translation process is configured to convert all the private IP addresses available to a single public IP address, but with a different port number assigned to each of the public addresses. Due to the process of translation, it is also known as NAT Overload.

Advantages and Disadvantages of NAT

Advantages:

• NAT provides privacy and security measures to the private address as our original network is translated to a public IP address.
• Is applied to conserve approved IP addresses over the network, and prevent wastage of IPv4 addresses.

Earn an Average Salary Hike of 70% in 6 Months!

PCP In Ethical Hacking And Penetration Testing

Explore Program

Disadvantages:

• NAT translation leads to path delay and prevents some application access for the private network model.
• The router should not tamper with port numbers according to the network protocols, but it has to due to the NAT translation process.

With the completion of this heading, we are now completed with this article on ‘Network Address Translation’.

Conclusion

In this article on ‘Network Address Translation’, we looked into the details of the address translation process, the steps involved in the NAT process, and its changes according to the type of network model applying the NAT services.

If you want to learn more about the topic and become more familiar with the network processes and configuration settings, you can refer to Simplilearn’s Cyber Security Expert course. With the completion of your professional training course, you’ll be equipped with the knowledge and work experience for the topic.

Do you have any questions about this article on ‘Network Address Translation’? If yes, feel free to mention them in the comment section at the bottom of this page. Our expert team will help you solve your queries at the earliest.